This invention relates to denture cleanser tablets and, more particularly, is directed to an improved completely water-soluble denture cleanser tablet containing enzymatic cleansing agents.
Denture cleanser tablets, in general, contain citric and tartaric acids and sodium bicarbonate, the interaction of of which generates carbon dioxide bubbles as the tablet dissolves when it is placed in water and thereby providing a mechanical cleansing action. Usually, to prevent the generated carbon dioxide bubbles from adhering to the dissolving tablet, they also contain an anti-foam silicone such as dimethyl polysiloxane thereby assuring that the tablet is continually acted upon by the water in which it is placed.
Denture cleanser tablets usually also have included therein one or more active oxygen compounds such as sodium perborate monohydrate, potassium persulfate, sodium carbonate peroxide, potassium peroxydiphosphate, diperisophthalic acid and the like, which cause the tablets to evolve micro-bubbles of active oxygen as they are dissolved in water and provide an oxidizing cleansing action. Generally, they also contain a surfactant to lower the surface tension and to enhance the cleansing action.
To form the dry active ingredients of the foregoing types into denture cleanser tablets of convenient size and compaction or of desired color and flavor, various other relatively inactive ingredients such as fillers, extenders, binders, colors or dyes and flavors, etc. are incorporated. Formulations for denture cleanser tablets also contain a lubricant system to facilitate smooth and even flow of the dry granular materials of the formulations during tabletting operations. In the past, such lubricant systems have generally been water insoluble substances such as magnesium stearate or talc; recently a more desirable water-soluble lubricant system consisting of an admixture of a spray dried magnesium lauryl sulfate powder and micronized polyethylene glycol polymer has been discovered and forms the subject matter of copending U.S. Application Ser. No. 482,403 filed June 24, 1974.
It has also been proposed in the past to include in denture cleanser tablets enzymatic cleansing agents to attack particularly the proteinaceous materials that are loosely bonded to the mucin and plaque that adhere to dentures in normal use. However, such enzymatic cleansing agents have not been usefully incorporated in denture cleanser formulations because of the inactivating effect of the active oxygen compounds on the enzyme during the shelf life period as well as in the water solution when the tablet is placed in water with the dentures to be cleaned.
Thus, it is apparent that a need exists for a denture cleanser tablet which will provide not only the usual cleansing abilities provided by the effervescence of carbon dioxide bubbles in water and the free active oxygen micro-bubbles but also an enzymatic cleansing action provided to attack the proteins, carbohydrates and fats that are loosely bound to the mucin and plaque adhering to dentures during normal use, and preferably to remove the plaque itself.